Prompt: Pen holder design, product design, simple and modern, its design inspiration comes from the nature of Ailurus (red panda, red panda, red cat bear) and tree trunk. The main body of the pen holder is a three-dimensional trunk, and the surface texture is fine mimicking the real bark. The top of the trunk is slit to form three branches of different heights. The end of each branch is designed with a small tree hole, which is both beautiful and practical for placing pens and other stationery. On this tree trunk, a delicate Ailurus sculpture is vividly displayed, as if exploring curiously or climbing easily. The whole color is mainly natural brown, which echoes with the hair color of Ailurus, creating a warm and comfortable office or learning environment. Solid color background, clean background, oc rendering,